摘要 |
A system (50) for controlling the temperature of recirculated exhaust gas supplied to an internal combustion engine (50). In one embodiment, the system (50) includes a heat exchanger (56) having the recirculated exhaust gas flowing therethrough and further having coolant fluid flowing therethrough. A control valve is disposed within the flow path of the coolant fluid, and the valve position is modulated to vary the rate of coolant fluid flow through the heat exchanger, thereby controlling the temperature of the recirculated exhaust gas supplied by the heat exchanger. In another embodiment, the heat exchanger defines a number of exhaust gas flow passages therethrough and a number of gas flow control valves are disposed between the exhaust gas inlet of the heat exchanger and the number of exhaust gas flow passages. The exhaust gas flow control valves are selectively actuated to disable exhaust gas flow through any number of subsets of the exhaust gas flow passages, thereby controlling the temperature of recirculated exhaust gas supplied by the heat exchanger. <IMAGE> |